There is no discussion that adversaries, past and present, have developed creative uses of the “full-spectrum” of warfare, including the use of regular and irregular tactics across all dimensions of war. Altogether this may well form a hybrid set of threats and strategy, but it is not clear why the term “hybrid” should be used, beside its mere descriptive value.
In practice, any threat can be hybrid as long as it is not limited to a single form and dimension of warfare. When any threat or use of force is defined as hybrid, the term loses its value and causes confusion instead of clarifying the “reality” of modern warfare.
Another issue with everything “hybrid” is that the use of a new term suggests there is something new about modern warfare - while this may not be the case. In his seminal book on Future Warfare, renowned military strategist Colin Gray convincingly argues that future, and by extension modern, warfare is essentially more of the same.
Most, if not all, conflicts in the history of mankind have been defined by the use of asymmetries that exploit an opponent’s weaknesses, thus leading to complex situations involving regular/irregular and conventional/unconventional tactics. Similarly, the rise of cyber warfare has not fundamentally changed the nature of warfare, but expanded its use in a new dimension.